Denim designs from laser scribing

ABSTRACT

A number of new laser patterns are defined by laser scribing the material. This produces new laser patterns which have not previously been known.

The present application is a continuation of U.S. application Ser. No.09/408,131, filed Sep. 29, 1999, now U.S. Pat. No. 6,495,237. It alsoclaims benefit from Provisional Application 60/102,363 filed Sep. 29,1998.

BACKGROUND

A major driving force for growth of the denim industry is the need fornew innovation and fashion. However, the current technology of producingand washing denim really only delivers one kind of product B blue jeans(or shorts or shirts) with two or three basic shades of blue.

Almost all jeans sold today in America are enzyme washed. The purpose ofthe enzyme wash is to remove some of the color from the rigid dark bluedenim and develop the cast and character of a stonewashed look.Depending upon the length of the enzyme wash cycle, the color of thefinal denim can range from light blue, medium blue or dark blue jeanswith one basic pattern result. The following excerpts taken from arecent article in Daily News Record (AGlut of Basic Denim Has MillsSearching for Fashion Appeal, Mar. 3, 1998) from leaders in the denimindustry illustrate the point:

Dutch Leonard, President of Burlington Global Denim, stated ARight nowthere is a world oversupply of denim in basics. We are shoring up ourparticipation in the added value segment of the denim business@. Hefurther reports that AWe are spending a lot of time with consumers tofind out what they want. What we have found is that consumers arelooking for something new and different.

Watts Carr, President of Cone Denim North America, indicates “Of coursetime will tell if consumers are willing to spend more for investmentjeans wear, but from what we've heard, the apparel makers are gettinginto it for the long run. And I think that we will see a broad-basedmovement that will impact jeans wear manufacturers across the board andhelp fend off some of the off-shore low-ball-priced business”.

Chris Glynn, Executive Vice-President of Greenwood, stated the only wayan American mill can survive is in added-value fabrics. The market isbig enough for a compromise between volume and innovation.

John Heldrich, President and Chief Executive Officer of Swift Denim,reported that at Magic, there was a lot of excitement around denim.Fashion items are what is doing well. The designer segment is drivinglighter weights and finishes, and newer brand names.

John Hudson, Jr., Executive Vice-President of Avondale, indicated thatthe key to success in today's denim business is low-cost manufacturingand innovation.

Hence, it can be seen that the denim market is crying for new denimproducts other than the three basic shades of blue. However, the enzymewashing process that is used to create the denim look simply does nothave the flexibility to produce a variety of different denim looks. Inaddition, the enzyme washing process has numerous drawbacks.

The true total cost for enzyme washing one pair of denim jeans is about$3 per pair when all unit cost and freight parameters are considered.The enzyme washing process significantly reduces (by about 36%) tensileand tear properties of the denim. In addition, the enzyme washingprocess produces numerous defects such as back pocket blowout thatresults in scrap or rework. The enzyme washing process uses as much as35 gallons of water per pair of jeans. In addition to all theseproblems, there are significant environmental problems associated withthe handling and disposal of the enzymes and wastewater.

U.S. Pat. No. 5,567,207 assigned to Icon, Inc. discloses a water freemethod for color fading textile materials with the use of a laser. Iconindicates that the wavelength of the laser should be chosen such that itis strongly absorbed by the dye, but not by the textile material. Iconused a Yag Laser for this purpose. Accordingly, the Icon patent teachesthat the Yag laser process will provide optimum dye photo-decompositionwhile not damaging the textile material. Icon, however, still onlytaught emulating the standard characteristics of certain conventiondenim design.

In our copending applications, and U.S. Pat. No. 5,916,461, TechnoLines,LLC. has shown that to produce the desired unique patterns, a CO2 laseris used which alters the surface chemistry of the fabric such that thefabric is indeed damaged, albeit at an acceptable level. For example,TechnoLines, Inc. has determined that the percent reduction in warptensile strength from a number of different new denim patterns createdwas from about 10 to about 20%. This is much better than theconventional enzyme washing process which reduces warp tensileproperties by about 36%. Therefore, the TechnoLines, LLC laser scribingprocess clearly but acceptably damages the textile material.

One possible look that has been desired and used by the industry is aseam abrasion look. This look forms a worn or ragged look on all theseams on a pair of jeans.

TechnoLines, LLC. has disclosed in our copending application that aspecific range of energy density per unit time, EDPUT, must becontrolled such that the various patterns withstand the vigors ofrepeated washings, yet maintain a bright image pattern.

SUMMARY

The present specification, for the first time, defines formations of newpatterns on denim. These new patterns are defined in detail herein, butmore specifically include areas of selectively faded areas of denim, andareas of non-selectively faded denim, collectively forming a pattern.

The pattern is a different pattern than that which would be produced bystone wash or acid washes.

One specific group of patterns includes patterns that repeat in acyclical arrangement, as compared with the stone washed/acid washedlook, which is substantially random in nature.

Another totally new group of patterns is a wallpaper type pattern,wherein cells of the pattern repeat in an offset way.

This is preferably done by varying critical operating parameters of thesystem, including power and speed (EDPUT), and oscillation andfrequency.

The inventor recognized two critical needs for a new denim process whichcan produce: 1) New denim patterns and looks using the current washingprocess but without enzymes and 2) Existing and new denim patterns witha process that eliminates the current kind of laundry processcompletely. Another aspect of this disclosure is to form a uniquepattern on a textile material, such as denim, using a laser using thesecontrolled parameters. That unique pattern simulates a random look suchas the look of a current enzyme washed product. The material is thenwashed using a conventional washing, without enzymes, but with desizingagents. The washing process can be part of an assembly line. Preferably,the lasing process is done using parameters which alter the surfacechemistry of the fabric such that the fabric is indeed damaged, albeitat an acceptable level.

As described above, the icon patent effects a water-free method to fadecolor. In contrast, this specification describes that some form ofwashing should be used to eliminate the residue on the denim sheet afterlaser scribing.

One such process disclosed by this application is the on-line washingprocess where the denim ribbon is lazed and then passed through feedrollers and a bath to wash and rinse the residue from the denimmaterial.

Alternately, the denim product could be sewn and washed with a desizingagent in a short wash and rinse cycle of about 10 minutes, as comparedwith the standard 60 plus minute cycle for enzyme washing. TechnoLines,Inc. actually lazed denim jean panels with several new and innovativelooks described below and then washed the panels in a conventionalnon-enzyme wash using a small amount of desizing agent and stones.

The seam abraded look can be obtained by incorporating stones into acommercial washer to achieve this effect. In fact, in one experimentTechnoLines, Inc. completed a lazed pair of denim jeans was washed in acommercial washer with a desizing agent and some stones. Surprisingly,after fifteen minutes, the denim product had a great looking lazedpattern with seam abrasion. In view of the above, the inventorrecognized two critical needs for a new denim process which canproduce: 1) New denim patterns and looks using the current washingprocess but without enzymes and 2) Existing and new denim patterns witha process that eliminates the current kind of laundry processcompletely.

One aspect described in this application is to form a unique patternwith a laser using controlled parameters including energy density perunit time and wobble. That unique pattern simulates the look of acurrent enzyme washed product. The material is then washed usingconventional washing, without enzymes, but with desizing agents. Thewashing process can be part of an assembly line. Preferably, the lasingprocess is done using parameters which alter the surface chemistry ofthe fabric such that the fabric is indeed damaged, albeit at anacceptable level. As described above, the Icon patent effects awater-free method to fade color. In contrast, this specificationdescribes that some form of washing should be used to eliminate theresidue on the denim sheet after laser scribing.

One such process disclosed by this application is the on-line washingprocess where the denim ribbon is lazed and then passed through feedrollers and a bath to wash and rinse the residue from the denimmaterial.

Alternately, the denim product could be sewn and washed with a desizingagent in a short wash and rinse cycle of about 10 minutes, as comparedwith the standard 60 plus minute cycle for enzyme washing. TechnoLines,Inc. actually lazed denim jean panels with several new and innovativelooks described below and then washed the panels in a conventionalnon-enzyme wash using a small amount of desizing agent and stones.

The seam abraded look can be obtained by incorporating stones into acommercial washer to achieve this effect. In fact, in one experimentTechnoLines, Inc. completed, a lazed pair of denim jeans was washed in acommercial washer with a desizing agent and some stones. Surprisingly,after fifteen minutes, the denim product had a great looking lazedpattern with seam abrasion.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects will be described with reference to theaccompanying drawings, wherein:

FIG. 1 shows a conveyer system for denim with a laser;

FIG. 2 shows a dual laser system with galvo mirrors that move the laseron the material;

FIG. 3 shows denim with feed rolls and an on-line washing system;

FIGS. 4 and 5 show laser lines scribed on denim;

FIG. 6 shows seam abrasion on denim; and

FIGS. 7-20 shows specific patterns that were made using the presentsystem.

DESCRIPTION OF THE EMBODIMENTS

In order to impart new patterns on denim, the entire desired surface ofthe denim is scribed using the laser. The basic layout is described inour copending application Ser. No. 08/550,339, the disclosure of whichis hereby incorporated by reference to the extent necessary for betterunderstanding.

FIG. 1 shows a first embodiment. A roll of denim material 99 is unrolledalong a working path, defining a denim “ribbon”. The laser 100 ismounted on a rail 105 along the width of the denim ribbon 99. The laserforms desired patterns in the material by traversing a path along thewidth of the denim ribbon 99 and applying a controlled energy densityper unit time (“EDPUT”) which intentionally damages the surface of thematerial in a way that changes the look of the material.

This operation is repeated in a continuous fashion to continuouslychange the look of the denim material.

A first embodiment scribes a periodic pattern on the material to form atotally new pattern on denim material. One or multiple lasers aremounted on the rails. If multiple lasers are used, the width of theribbon 99 for each laser to scribe a specific section of the width orthe total width per one traverse of the laser.

FIG. 3 shows that the laser can also be mounted over the cutting tableand one or more lasers can scribe the patterns on the various denimpanels. In this case, the scribing movement is via the galvanometricmirrors in the laser. Of course, the galvometric mirrors could also beused in the first example to scribe a pattern on denim in a continuousfashion as the denim is rolled from the roll at the textile mill asshown in FIG. 4.

Even though the material has been changed in look, removal of thedesizing agent may still be desireable. In order to allow this operationwithout a separate washing operation, the laser-scribed product can thenbe be washed in a mild desizing agent as part of the processing. FIG. 5shows this being washed as part of the on-line processing.

Turning now to the more specific, a number of specific new designs havebeen made using this technique. This has produced totally new lookswhich have never before been possible. Each of these new looks has beenmade by carefully controlling a wide variety of laser operatingparameters including frequency, oscillation, power, speed, and focaldistance.

The parameters of the laser are controlled to make these designs. Theseparameters include:

Frequency, which controls the pulse duty cycle of the laser. A lowerfrequency lowers the number of pulses per unit time. The frequency of999 is close to continuous wave (“cw”). The Q switch on the laserdetermines the amount of frequency that is emitted.

Power controls the percentage of power that is emitted by the laser,compared with the pump source's maximum output power.

Speed is the rate at which the beam travels across the lasing medium.

Beam spot is the size of the laser beam that is emitted.

Image density is the proximity of fill lines; usually a linear placementthat determines the contiguousness of the image.

Note that speed and frequency determine the size of the heat affectedzone (“HAZ”), which in turn determines the marking line width.Increasing the line width, by slow speed and/or high frequency,decreases the image density but increase the surface temperature. Thisincreases the thermal breakdown of the material.

Wobble is the shaking motion of the galvo mirrors in the laser. Thiscreates a movement from the center point in units of 0-3 mm. Twoparameters control wobble: the waveform that defines the geometry of thetrace (sine, square), and amplitude.

The designs described herein were formed with a laser from Excel, Stylusmodel. As measured, the speed” parameter is approximately in inches persecond (a speed of 30 marked 12 inches in a second). Wobble defines theamount of oscillation of the laser. A 0.02 wobble produces anoscillation of about 1 mm, which repeats differently depending on thespeed. At a speed of 30, the wobble repeats every 3.7 mm. At a speed of40, the wobbling repeats every 6.5 mm. A wobble value of 0.04 producesan oscillation of about 2 mm, which, at speed 30, repeats approximatelyevery 4.1 mm approximately.

Several striking exemplary denim designs were produced as shown in FIGS.6-20. These designs are completely new within the field of denim design.

FIG. 6 shows a unique design of vertical stripes called “StrollerStripe”. This is formed of a number of stripes where the denim has beenlightened by the laser. Within each stripe is a filled in portion whichis not completely filled in, but is shaded by wobble of the laser. Thiswobble shades by forming a pattern of offset spirals in between theouter edges defining the stripe edges.

FIG. 7 shows a spotted pattern called “Broken Birdseye”. This includes apattern that is randomly spotted with lightened areas.

FIG. 8 shows a boxed pattern called “Honeycomb”. This is a repeatingpattern of honeycomb-surrounded shapes, with lightened spots in eachhoneycomb cell.

FIG. 9 shows a wallpaper type pattern called “Sand Crepe”. This haspattern cells which repeat on the material, but are offset relative toone another. Each of the generally trapezoidal shapes is in a specifiedpattern. FIG. 10 shows a “Zig Zag” pattern where the overall patternforms a zig zag. The material is lightened in areas between the darkenedzig zag pattern outline. The lightened portion is preferably filled inby a spiral pattern.

FIG. 11 shows a “Vertical Ladder” pattern. The areas between cellsremains dark, and the center of the cells is filled.

FIG. 12 shows a “Tuxedo Look” pattern with light stripes of material.

FIG. 13 shows a “Twisted Fiber” pattern that includes alternate lightand dark areas.

FIG. 14 shows an “Angled Ladder” pattern with polygonal shapes, each ofwhich is defined by internal cycloided pattern parts.

FIG. 15 shows a “Diamond” pattern with alternate light and dark areas,each area being substantially sinusoidal in shape.

FIG. 16 shows a “snakeskin” pattern where each pattern part is a squareoutlined in darker portion, the interior of which is defined by anon-filled shape.

FIG. 17 shows a “Ruff Hewn Look” pattern with darker dividing areasseperating lighter interior portions.

FIG. 18 shows a “Shotgun Blast” pattern which is speckled.

FIG. 19 shows a “High Ridged Look” pattern, also speckled.

FIG. 20 shows a “Ribbed Look” pattern which has lighter and darker spotsarranged in ribs.

In all of these patterns, there are light spots on the denim caused bythe laser damaging the material and giving it a lighter look. Theselight spots are interspersed with darker areas where either the laserhas not altered the original color of the material, or has less alteredthe original color thereby leaving the material darker in those areas.

Totally new looks include repeating patterns, repeating polygonal/squarepatterns, pattern areas that are filled with “wobbled” patterns, that isthose that repeat in an offset sinusoidal or cycloid shape to formalternately light and dark areas, and others.

The specific laser operating parameters which resulted in the productionof these novel denim looks is given in Table 1.

TABLE I Laser Operating Parameters for the Production of Unique DenimDesigns Pattern Denim Power Speed Fre- Wobble Density Miscell- Pattern(Watts) (in/sec) quency (in) (%) aneous Stroller 69 6 .009 .02 50 StripeBroken 99 20 70 TechnoBlast Birdseye pattern Honey- 69 45 .009 100Double Pass comb SandCrepe 59 20 .015 .02 100 ZigZag 69 30 .009 100Double Pass Vertical 69 10 .009 .02 50 Ladder Tuxedo 99 20 75 45 degreeorientation Twisted 59 10 .009 .02 35 Fiber Angled 69 14 .009 .02 50Ladder Diamond 59 29 .015 .02 100 Snakeskin 69 25 .009 100 Ruff 99 16.02 33 TechnoBlast Hewn pattern Shotgun 59 7 .009 .02 35 TechnoBlastBlast Pattern High 99 23 .02 75 Ridged Look Ribbed 99 26 75 45 degreeorientation

As can be seen from the above chart, the characteristics of the patternsinclude power between around 60-100 watts, speed of about 6-50 inchesper second, frequency between 0.009 and 0.015, wobble of either 0 or0.02, and pattern density between 33 and 100.

Significantly, the tensile and tear properties of the denim followinglaser scribing and conventional washing is markedly superior to that ofthe denim following normal enzyme washing. Table II shows theimprovement in physical properties associated with the laser scribingprocess and conventional washing process vs. the normal enzyme washingprocess. The conventional enzyme washing process for denim reduces warptensile properties by about 36% whereas the laser scribing process toproduce new denim patterns followed by conventional home washing reducesthe tensile tear properties anywhere from about 10 to about 20% (for allbut one of the patterns in which a heavy laser scribe reduced warptensile properties by 29%).

TABLE II Tensile Properties of New Denim Products Made from TechnoLines,Inc. Laser Scribing Process and Washed in a Conventional Home WashingMachine vs. Traditional Dean Products Enzyme Washed. Product WarpTensile (lbs) Percent Loss Rigid 14.75 oz Denim 193 Enzyme Washed Denim123 36.3 Broken Birdseye 174 9.8 (Light Laser Scribe) Broken Birdseye161 16.6 (Medium Laser Scribe) Broken Birdseye 137 29.0 (Heavy LaserScribe) SandCrepe 159 17.6 (Light Laser Scribe) Sand Crepe 154 20.2(Medium Laser Scribe) Sand Crepe 153 20.7 (Heavy Laser Scribe) Honeycomb168 12.9 (Light Laser Scribe) Honeycomb 168 12.9 (Medium Laser Scribe)Honeycomb 158 18.1 (Heavy Laser Scribe)

Although only a few embodiments have been described in detail above,those of skill in the art recognize that many modifications are intendedand predictable from the disclosed embodiments. For example, otherpatterns are possible by suitable variations in the parameters asdescribed herein. These patterns, however, broadly fall into twocategories: a pattern formed by a cyclical process which appears to haverandom parts, and a pattern formed by the cyclical process which hasrepeating parts.

While the process described herein contemplates denim as being thepreferred material, it should be understood that any fabric or materialcould be used.

All such modifications are intended to be encompassed within thefollowing claims.

1. A method, comprising: setting specified parameters on a controllablelaser, said specified parameters being parameters which control anamount of energy that is applied to a denim workpiece to alter a surfacechemistry of the denim in a way to change the look of the denimaccording to a pattern without undesirably damaging the denim; and usingsaid controllable laser to modify the look of an entire width of a denimarticle per single traverse of the laser as the output of the laserpasses across the denim article.
 2. A method as in claim 1, wherein thedenim article is an item of denim apparel.
 3. A method as in claim 1,wherein the denim article is a roll of denim a material that is unrolledto form a denim ribbon.
 4. A method as in claim 1, wherein the specifiedparameters include an image density of lines that are formed on thedenim.
 5. A method as in claim 1, wherein the specified parameterscontrol geometry of the output of the laser.
 6. A method as in claim 1,wherein said using comprises using said laser along a conveyer andfurther comprising washing the denim along said conveyor after saidusing.
 7. A system comprising: a material holding part, which holds aworkpiece to be processed; a controllable laser, which is controllableaccording to specified parameters which control power output andposition of the laser to alter a surface chemistry of the workpiecewhere an entire width of the workpiece is altered per single traverse ofthe laser.
 8. A system as in claim 7, wherein the workpiece is a denimapparel article.
 9. A system as in claim 7, wherein the workpiece is aroll of denim material.
 10. A system as in claim 9, further comprising aconveyor system, and wherein the roll of denim material is unrolledalong said conveyor system.
 11. A system as in claim 10, furthercomprising a washing station along the conveyor system.
 12. A system asin claim 7, wherein the specified parameters control a line width ofmarking by the laser material.
 13. A method, comprising: settingspecified parameters on a controllable laser, said specified parametersincluding an energy density per-unit time that marks a denim materialwithout undesirably damaging the denim material, wherein said markingcomprises changing a look of the denim material in a way which can beseen by a user, and wherein said specified parameters compriseparameters which causes a pattern to be formed on said denim whichpattern repeats across an entire unit area of said denim; and using thecontrollable laser to modify the look of the denim according to saidspecified parameters to form a plurality of unit area patterns on thedenim.
 14. A method as in claim 13, wherein the denim material is adenim apparel.
 15. A method as in claim 13, wherein the denim materialis a roll of denim material that is unrolled during said using.
 16. Amethod as in claim 15, further comprising using the controllable laseralong a conveyor system.
 17. A method as in claim 16, further comprisingwashing the denim material along the conveyor.